N54 Turbocharger LHD and RHD: clarity on the difference

[Bimmer Paul]

When I was buying some second-hand turbo's, obviously there were a lot of options from the USA on ebay; as I'm sure any owner with a modified N54 will know, it seems to be harder to find the same level of modification options over here in the UK (or specifically for RHD cars), most the immediate options that pop up are from America or Germany which are often for LHD cars.

Anyway, I have seen a few a posts on various forums asking about the differences between the RHD vehicle turbochargers and the LHD versions, with lots of responses, but nothing definitive to let you know if the turbo in your hand was actually the right one!  (There is even a video on you-tube showing both versions, but rather un-helpfully no audio to tell you which is which!).  So I wanted to post a very clear description of the differences as when I tried to find this out before buying a second hand pair, it wasn't as easy as you might hope.  Now hopefully anyone else making this search in the future will come across this post and be re-assured at what they are buying.

So, the front turbo's, i.e. the turbo for cylinders 1-3 are actually identical on both RHD and LHD vehicles.  Think everyone knew that.  The rear turbo's are indeed different to allow for the steering column, so are NOT interchangeable 'across the pond' and the differences are as follows:

RHD: we have a longer wastegate actuator over here in the UK, that when looking directly at the turbo and side-on at the engine, the wastegate actuator points DOWN and left, i.e. by 'down' I literally do mean towards the floor and towards the bulkhead of the car (and away from the exhaust manifold). 

 

This matches the general path of the front turbocharger wastegate, i.e. it travels towards the floor but this time towards the bumper and also ends up further away from the exhaust manifold than where it started (albeit the assembly is mirrored and the arm is on the opposite side of the turbocharger and hidden from view when on the vehicle). 

So if you have two very similar looking turbochargers with similar wastegate arms that operate downwards but are basically mirror versions of each other: then you have a set of RHD N54 turbocharger's.

LHD: the USA rear turbo has a much shorter wastegate actuator that points UP and left, so the wastegate is ends up much closer to the exhaust manifold and travels upwards to the bonnet and towards the bulkhead of the vehicle.

Hence if you have turbo's with one wastegate actuator significantly shorter than the other with the actuator operating upwards instead of downwards, these are a set of LHD turbochargers.

 

I hope this post helps at least one google searcher one day!

 

[Bimmer Owners Club]

Thanks Paul....that is an awesome description and a fantastic bit of information that will definitely help others to determine the correct installation.

I will move this to the Guides section as well as leave a copy here

 

[Bimmer Paul]

Thanks Trevor!